- [Voiceover] So really the main sort of
underlying goal of stroke treatment is really
to save as much brain tissue as possible.
As you probably thought, right?
Because by saving the maximum amount of brain
tissue, the idea is that we only lose a minimal
amount of function, of bodily function,
movement, vision, sensation, taste even.
So, you might remember that in any ischemic stroke
there's a core area of neurons right at the site
of the blood vessel obstruction,
so there's brain tissue there that'll usually
be irreversibly damaged within a few minutes
of losing their blood supply.
So, that's not great, but the good news is that
there's salvageable brain tissue surrounding
that core called the penumbra.
So, this is an area where blood profusion
has gone down because of the blockage here,
but since it's still getting oxygen sort of
peripherally from these blood vessels in the areas
around it, these penumbra neurons don't die off
right away, and if the person gets quick enough
treatment then the penumbra neurons don't die
off at all in most cases, the penumbra is savable.
So, when someone comes in having had a stroke,
the healthcare team often is thinking,
"Alright, let's get down to business and
"try to save the core if possible,
"and let's definitely save that penumbra before
"it's too late."
So, with all that said, what sort of treatment
can you get after a stroke?
Well, remember that depends on what type
of stroke you've had, ischemic or hemorrhagic.
And with ischemic strokes you're usually given
aspirin to prevent new clots from forming
and thromobylics which try to break up
the existing clot.
And with hemorrhagic it's more about managing
symptoms and potential complications in the
initial phases of this stroke.
Sometimes with an antihypertensive to lower
blood pressure, and thus the amount of bleeding
that's happening in the brain,
and sometimes with an anticonvulsant to prevent
any possible seizures, and sometimes with drugs
to reduce swelling in the brain.
So a few different medication options for these
two types of strokes, but what else can be done?
I mean, we've all seen McDreamy the neurosurgeon
rush into the O.R. with his fancy hair,
and his "it's a great day to save lives" spiel,
what's he up to?
By the way, he's the neurosurgeon from the
thrilling drama "Grey's Anatomy".
In the case of ischemic strokes, the surgeons won't
usually be called to surgery unless the patient
isn't responding to thrombolytics.
So thrombolytics are usually tried first
if the patient's still within the few hour window
that they work best in.
Otherwise if the surgeons are treating a patient
with an ischemic stroke, they might be doing one of
a few different but similar types of procedures
with the ultimate goal of removing the clot
that causes a stroke.
So, one little device that they might use is
called the "MERCI Retriever", and this was
actually the first ever little gadget that was
approved for clot removal after ischemic stroke.
So, let's look at what MERCI stands for
to get an idea of how it works.
MERCI's an acronym, right?
So it stands for Mechanical Embolus
Removal in Cerebral ischemia.
And how does it work?
Well, let's just look at the general idea
instead of bogging you down with all the
technical details here.
So, essentially what happens is that
as part of this procedure a surgeon will insert
a little wire into an artery and sort of thread
it up into the brain, guide it along the arteries
and get up into the brain here.
And then the wire gets pushed just past the clot
and that thing in blue there is actually
a little sheath, the wire is actually inside
the sheath, and then when the sheath gets
retracted the wire starts to actually coil
up on its own.
And then as the wire is slowly retracted,
as you can probably imagine it'll sort of catch
on to the clot, it'll grab onto the clot
nice and tight.
And then the wire and the clot together
they're both removed, and now blood can
perfuse this area again and try to save
all this brain tissue here.
So that's MERCI retrieval, it's pretty cool stuff.
And another way that ischemic strokes can be
treated surgically is with suction.
So how does that work?
Well again here, same sort of deal.
A tube goes into the artery and from here a
little wire is put through the tube and positioned
so it's right behind the clot.
Then this tube sort of turns into a little vacuum
cleaner that starts to suck in, and while it's
sucking in, a wire gets pushed back and forth
a few times through this clot to break it up.
And all the little pieces that break off and
eventually the whole thing, the whole clot
gets sucked into this little vacuum here.
So that's the suction method.
And so there's a few other little variations
on these two procedures for clot removal,
you know, some using little mesh tubes
called "stents" and some others with some
different mechanisms but I'll leave it at this
for now.
So those two that we just talked about,
those are treatments for ischemic strokes,
but if our surgeon was treating a hemorrhagic
stroke where one of the major goals is to
control the bleeding, he might be doing some
other things, some different procedures.
So there's one called "aneurysm clipping".
And what that is is, well we know that if an
aneurysm in the brain bursts or sort of ruptures,
then it'll start to spill blood out into the
brain space right?
Well, one way to fix that is for the surgeon
to place a clip that kind of looks like this
thing here, it's like a metal clip that then
gets clamped on to the base of the aneurysm.
So now that clip has blocked blood from coming
through here and spilling out, so now blood can
just continue along its merry little way, right?
So, that's one way to treat a hemorrhagic
stroke with these clips.
Another procedure a neurosurgeon might do,
and again this is in cases where a hemorrhage
was caused by a burst aneurysm,
is something called "Coil Embolization",
and in coil embolization you'll kinda see
why this name is fitting in a minute here.
The surgeon will insert a little tube into
the arterial system again, we're back to the tubes
again so it'll get threaded up into the cerebral
arteries until it's basically right inside the
aneurysm right at the mouth of the aneurysm.
And then, this flexible little wire gets
threaded in through the tube and it starts to now
coil up inside the dilated out part of the
artery, the aneurysm here.
And then more and more wire gets pushed in
through the tube and into the aneurysm and it
just coils and coils and coils.
And eventually blood now can't even really enter
that aneurysm even if it wanted to.
So, two things.
One, blood can now start to clot right?
It can start to clot onto all this material
in the aneurysm here and stop any bleeding
from happening, so awesome, thumbs up.
And two, blood in this artery here now it doesn't
even have the option to duck up into this
aneurysm and cause trouble anymore because
of this clotted up coil.
So now blood just continues to go about its
business I guess down over this way.
So, double thumbs up.
So, those are some of the surgical interventions
for ischemic and hemorrhagic stroke treatment.